I never thought logging two accounts into one computer was a problem. I knew people who did it and were fine. So I took the lazy route: two tabs in the same Chrome window. Personal on the left, business on the right, switch back and forth. Convenient.
The next morning, the left account asked me to solve an image captcha. The right one showed a disabled notice. One could be saved. The other could not.
I thought they were two accounts. They were in the same house
Later I understood that accounts are not separated by names. They are separated by devices, browsers, and networks. Logging two accounts into one browser is two people talking in the same room on the same phone.
Cookies are the obvious thread. Two tabs in one browser share cookies. Add the same hardware, the same screen size, the same fonts, the same IP, and the platform can draw a line connecting them without much effort.
I thought I had two doors. I had one hallway.
Dumb things I did on top of that
I liked and commented between the two accounts to make them look "real." Two accounts on the same IP liking each other and then never interacting otherwise is a strange pattern in itself.
I also used the same phone number to verify both. That line was even more direct. I basically reported myself.
How I separate them now
I do not use one device for two accounts. If I have to work on one computer, I use separate browsers or an isolated profile. Each account gets its own cookies, cache, and timezone settings.
Networks are separate too. One exit for this account, another for that one. I do not switch back and forth within the same minute. There is a gap.
That was also when I started checking exits. The IP lookup for ownership, the proxy check for proxy traits. Knowing what you are standing on beats guessing.
Do not rush the interaction
New accounts should not like, follow, or comment on each other. People think this "warms them up." It mostly hands the platform clues. Mine now live separate lives and do not know each other.
If two accounts must be connected, let it be a real connection, like the same real person's details. Fake relationships do not survive inspection.
The end
The business account never came back. The personal one survived verification, but I no longer switch between them casually. Two accounts on one PC looks convenient. It is digging your own hole.
If you are about to do it, pause. Separating them costs far less than rebuilding both.